In recent years, smartphones, digital audio players, portable game machines, tablet-type terminals, and the like that incorporate a touch panel display device are in wide use. Using a touch panel allows more intuitive inputs to be made via a screen. Using a touch panel also provides an advantage of being able to reduce the number of physical buttons to be provided on the electronic device. Therefore, it is considered that touch panels will remain as promising input devices, particularly for various small-sized electronic devices that are portable.
The number of users of smartphones having a touch panel is only increasing every year. Under such circumstances, there are growing opportunities to manipulate a touch panel while holding a smartphone in one hand. When manipulating a smartphone with one hand, it is often the case that the touch panel is manipulated with the thumb, while the body is supported with the palm, the middle finger, the ring finger, and the like.
In the present specification, the term “touch panel” may also refer to no more than a position input device (also called a touch sensor, a touch pad, etc.) which is provided on a display device, without including the display device.